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<head><meta charset="utf-8"><title>ad hoc triage meeting 2020.04.10 #54818 · t-compiler · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/index.html">t-compiler</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html">ad hoc triage meeting 2020.04.10 #54818</a></h3>

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<a name="193574123"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574123" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574123">(Apr 10 2020 at 14:24)</a>:</h4>
<p>fresh topic</p>



<a name="193574212"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574212" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574212">(Apr 10 2020 at 14:26)</a>:</h4>
<p>first, nominations: <a href="https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AI-nominated+label%3AT-compiler" title="https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AI-nominated+label%3AT-compiler">https://github.com/rust-lang/rust/issues?q=is%3Aopen+label%3AI-nominated+label%3AT-compiler</a></p>



<a name="193574280"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574280" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574280">(Apr 10 2020 at 14:26)</a>:</h4>
<p>nom 1/8: "ICEs should always print the top of the query stack." <a href="https://github.com/rust-lang/rust/issues/70953" title="https://github.com/rust-lang/rust/issues/70953">#70953</a></p>



<a name="193574291"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574291" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574291">(Apr 10 2020 at 14:26)</a>:</h4>
<p>we discussed <a href="https://github.com/rust-lang/rust/issues/70953" title="https://github.com/rust-lang/rust/issues/70953">#70953</a> yesterday I believe</p>



<a name="193574295"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574295" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574295">(Apr 10 2020 at 14:26)</a>:</h4>
<p>I think we w- yeah</p>



<a name="193574351"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574351" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574351">(Apr 10 2020 at 14:27)</a>:</h4>
<p>(just trying to be thorough/mechanical, as I am a replicant after all)</p>



<a name="193574362"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574362" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574362">(Apr 10 2020 at 14:27)</a>:</h4>
<p><span class="user-mention" data-user-id="133247">@bjorn3</span> suggested always emitting backtraces but I recall there being issues with that. but maybe they've been fixed</p>



<a name="193574380"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574380" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574380">(Apr 10 2020 at 14:27)</a>:</h4>
<p>(e.g. <code>libbacktrace</code> used to be much slower IIRC)</p>



<a name="193574395"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574395" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574395">(Apr 10 2020 at 14:27)</a>:</h4>
<p>yeah. I think there was general support for the idea? Anyway if anyone objects, please post on issue itself</p>



<a name="193574407"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574407" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574407">(Apr 10 2020 at 14:27)</a>:</h4>
<p>nom 2/8: "Fix staticlib name for *-pc-windows-gnu targets" <a href="https://github.com/rust-lang/rust/issues/70937" title="https://github.com/rust-lang/rust/issues/70937">#70937</a></p>



<a name="193574418"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574418" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574418">(Apr 10 2020 at 14:27)</a>:</h4>
<p>If there are no major issues, that would be great to always print it <span aria-label="+1" class="emoji emoji-1f44d" role="img" title="+1">:+1:</span></p>



<a name="193574429"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574429" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574429">(Apr 10 2020 at 14:27)</a>:</h4>
<p>we also discussed <a href="https://github.com/rust-lang/rust/issues/70937" title="https://github.com/rust-lang/rust/issues/70937">#70937</a> yesterday</p>



<a name="193574481"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574481" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574481">(Apr 10 2020 at 14:28)</a>:</h4>
<p>there were no objections but a general feeling that this area needs an owner?</p>



<a name="193574528"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574528" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574528">(Apr 10 2020 at 14:28)</a>:</h4>
<p>so if you have objections to <a href="https://github.com/rust-lang/rust/issues/70937" title="https://github.com/rust-lang/rust/issues/70937">#70937</a>, please post on the ticket</p>



<a name="193574540"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574540" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574540">(Apr 10 2020 at 14:28)</a>:</h4>
<p>Maybe we should reach out to the winapi crate owner</p>



<a name="193574550"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574550" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574550">(Apr 10 2020 at 14:29)</a>:</h4>
<p>is that retep?</p>



<a name="193574551"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574551" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574551">(Apr 10 2020 at 14:29)</a>:</h4>
<p>we could use more windows experts</p>



<a name="193574562"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574562" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574562">(Apr 10 2020 at 14:29)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> believe so</p>



<a name="193574571"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574571" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574571">(Apr 10 2020 at 14:29)</a>:</h4>
<p>about this specific change, or about being a windows owner?</p>



<a name="193574580"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574580" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574580">(Apr 10 2020 at 14:29)</a>:</h4>
<p>windows owner</p>



<a name="193574591"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574591" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Wesley Wiser <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574591">(Apr 10 2020 at 14:29)</a>:</h4>
<p>They got cc'd on the issue</p>



<a name="193574600"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574600" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574600">(Apr 10 2020 at 14:29)</a>:</h4>
<p>ah <span aria-label="+1" class="emoji emoji-1f44d" role="img" title="+1">:+1:</span></p>



<a name="193574612"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574612" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574612">(Apr 10 2020 at 14:29)</a>:</h4>
<p>I think in the past we've let e.g. acrichto handle stuff like this but it always lead to having a lot on their plate</p>



<a name="193574681"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574681" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574681">(Apr 10 2020 at 14:30)</a>:</h4>
<p>They have less on their plate now <span aria-label="slight smile" class="emoji emoji-1f642" role="img" title="slight smile">:slight_smile:</span></p>



<a name="193574688"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574688" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574688">(Apr 10 2020 at 14:30)</a>:</h4>
<p>I can reach out to retep, see if they object to being our domain expert here</p>



<a name="193574723"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574723" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574723">(Apr 10 2020 at 14:30)</a>:</h4>
<p>(I think achricto has plenty on their plate, its just hidden behind NDAs)</p>



<a name="193574757"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574757" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574757">(Apr 10 2020 at 14:30)</a>:</h4>
<p>but what do I know</p>



<a name="193574768"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574768" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574768">(Apr 10 2020 at 14:31)</a>:</h4>
<p>IOW I think having dedicated experts is better than just throwing everything nobody else in the compiler team can handle in the general direction of one person</p>



<a name="193574805"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574805" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574805">(Apr 10 2020 at 14:31)</a>:</h4>
<p>nom 3/8: "[WIP] Rename mir::Rvalue to Op." <a href="https://github.com/rust-lang/rust/issues/70928" title="https://github.com/rust-lang/rust/issues/70928">#70928</a></p>



<a name="193574810"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574810" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574810">(Apr 10 2020 at 14:31)</a>:</h4>
<p>oh boy this one</p>



<a name="193574832"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574832" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574832">(Apr 10 2020 at 14:31)</a>:</h4>
<p>what was motivation here?</p>



<a name="193574833"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574833" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574833">(Apr 10 2020 at 14:31)</a>:</h4>
<p>so we started doing some renames years ago</p>



<a name="193574845"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574845" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574845">(Apr 10 2020 at 14:31)</a>:</h4>
<p>My reaction to this PR is sorta: "but why?"</p>



<a name="193574847"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574847" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574847">(Apr 10 2020 at 14:31)</a>:</h4>
<p>we got rid of "lvalue" and "rvalue" in rustc</p>



<a name="193574904"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574904" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574904">(Apr 10 2020 at 14:32)</a>:</h4>
<p><em>except</em> we sort of left <code>mir::Rvalue</code> behind</p>



<a name="193574928"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574928" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574928">(Apr 10 2020 at 14:32)</a>:</h4>
<p>We use Value vs. Place in the reference and UCG</p>



<a name="193574932"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574932" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574932">(Apr 10 2020 at 14:32)</a>:</h4>
<p>so it's just sitting there, orphaned from "official terminology"</p>



<a name="193574939"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574939" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574939">(Apr 10 2020 at 14:32)</a>:</h4>
<p>right</p>



<a name="193574954"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574954" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574954">(Apr 10 2020 at 14:32)</a>:</h4>
<p>(I didn't like it much, but I've accepted it ^^)</p>



<a name="193574955"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574955" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574955">(Apr 10 2020 at 14:32)</a>:</h4>
<p>I think <span class="user-mention" data-user-id="126931">@centril</span> 's argument on the ticket that <code>Op</code> is far harder to grep for than <code>Rvalue</code> is a very strong case</p>



<a name="193574971"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574971" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574971">(Apr 10 2020 at 14:33)</a>:</h4>
<p><code>\bOp\b</code> :P?</p>



<a name="193574983"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574983" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574983">(Apr 10 2020 at 14:33)</a>:</h4>
<p>but okay yeah it's probably too short</p>



<a name="193574986"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574986" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574986">(Apr 10 2020 at 14:33)</a>:</h4>
<p>(in particular because <code>Op</code> is a prefix of <code>Operand</code>)</p>



<a name="193574992"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193574992" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193574992">(Apr 10 2020 at 14:33)</a>:</h4>
<p>My personal preference is that we leave it be as is</p>



<a name="193575014"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575014" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575014">(Apr 10 2020 at 14:33)</a>:</h4>
<p>bikeshed-wise I don't care too much what we rename it to, it just reminds me every time I see it of a job not finished</p>



<a name="193575025"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575025" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575025">(Apr 10 2020 at 14:33)</a>:</h4>
<p>(or at least wait until we come up with a better new name)</p>



<a name="193575029"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575029" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575029">(Apr 10 2020 at 14:33)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> hmm can we use an FCP to "vote" on this?</p>



<a name="193575042"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575042" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575042">(Apr 10 2020 at 14:33)</a>:</h4>
<p>I guess so</p>



<a name="193575073"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575073" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575073">(Apr 10 2020 at 14:34)</a>:</h4>
<p>I guess that doesn't account for the bikeshed aspect</p>



<a name="193575147"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575147" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575147">(Apr 10 2020 at 14:34)</a>:</h4>
<p><code>Operation</code> is the direct longform alternative</p>



<a name="193575161"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575161" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575161">(Apr 10 2020 at 14:34)</a>:</h4>
<p>should I do an rfcbot fcp close, or fcp postpone ...</p>



<a name="193575177"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575177" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575177">(Apr 10 2020 at 14:35)</a>:</h4>
<p>Does "Operation" make semantic sense?</p>



<a name="193575180"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575180" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575180">(Apr 10 2020 at 14:35)</a>:</h4>
<p>I think close is the right thing here</p>



<a name="193575186"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575186" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575186">(Apr 10 2020 at 14:35)</a>:</h4>
<p>heh I forget it has that many options</p>



<a name="193575198"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575198" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575198">(Apr 10 2020 at 14:35)</a>:</h4>
<p><span class="user-mention" data-user-id="126931">@centril</span> it's an operation on operands that produces a value</p>



<a name="193575205"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575205" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575205">(Apr 10 2020 at 14:35)</a>:</h4>
<p>Operation feels more "impure" to me (terminatorkind)</p>



<a name="193575241"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575241" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575241">(Apr 10 2020 at 14:35)</a>:</h4>
<p><span class="user-mention" data-user-id="119009">@eddyb</span>  fair</p>



<a name="193575322"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575322" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575322">(Apr 10 2020 at 14:36)</a>:</h4>
<p><code>Operator</code> would be confusing because of the expectation of"operator is either  unary or binary (but not other things)", but kind of funny to consider</p>



<a name="193575377"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575377" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575377">(Apr 10 2020 at 14:36)</a>:</h4>
<p>"Rvalue" seems memorable and sorta unique at least</p>



<a name="193575395"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575395" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575395">(Apr 10 2020 at 14:36)</a>:</h4>
<p>Should we move on?</p>



<a name="193575433"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575433" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575433">(Apr 10 2020 at 14:37)</a>:</h4>
<p>(if we're bikeshedding, I'd be curious to know if <code>Expr</code> is taken)</p>



<a name="193575439"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575439" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575439">(Apr 10 2020 at 14:37)</a>:</h4>
<p>anyway</p>



<a name="193575440"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575440" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575440">(Apr 10 2020 at 14:37)</a>:</h4>
<p>it's not</p>



<a name="193575447"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575447" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575447">(Apr 10 2020 at 14:37)</a>:</h4>
<p>better to move on, before it sinks in that I should've just finished the job years ago :P</p>



<a name="193575463"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575463" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575463">(Apr 10 2020 at 14:37)</a>:</h4>
<p>nom 4/8: Compile regression "cannot infer an appropriate lifetime for lifetime parameter" <a href="https://github.com/rust-lang/rust/issues/70917" title="https://github.com/rust-lang/rust/issues/70917">#70917</a></p>



<a name="193575471"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575471" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575471">(Apr 10 2020 at 14:37)</a>:</h4>
<p>this is once again a lang team nom, right? <span aria-label="wink" class="emoji emoji-1f609" role="img" title="wink">:wink:</span></p>



<a name="193575519"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575519" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575519">(Apr 10 2020 at 14:38)</a>:</h4>
<p>pretty sure we discussed it last night</p>



<a name="193575525"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575525" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575525">(Apr 10 2020 at 14:38)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> lang did discuss; so now it is t-compiler</p>



<a name="193575531"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575531" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575531">(Apr 10 2020 at 14:38)</a>:</h4>
<p>yeah and we're waiting on a crater run</p>



<a name="193575546"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575546" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575546">(Apr 10 2020 at 14:38)</a>:</h4>
<p>so nothing to discuss yet</p>



<a name="193575554"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575554" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575554">(Apr 10 2020 at 14:38)</a>:</h4>
<p>oh wow I love that ability</p>



<a name="193575561"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575561" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575561">(Apr 10 2020 at 14:38)</a>:</h4>
<p>other than to report the lang team findings</p>



<a name="193575566"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575566" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575566">(Apr 10 2020 at 14:38)</a>:</h4>
<p>I will try to make a point-release for <code>proptest</code></p>



<a name="193575582"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575582" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575582">(Apr 10 2020 at 14:38)</a>:</h4>
<p>(to just run crater on arbitrary PRs after the fact)</p>



<a name="193575583"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575583" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575583">(Apr 10 2020 at 14:38)</a>:</h4>
<p>That's not really "t-compiler", but I guess it is, a bit? :D</p>



<a name="193575606"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575606" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575606">(Apr 10 2020 at 14:39)</a>:</h4>
<p>nom 5/8: <code>forbid</code> overwritten by later <code>allow</code> on the same "scope level" <a href="https://github.com/rust-lang/rust/issues/70819" title="https://github.com/rust-lang/rust/issues/70819">#70819</a></p>



<a name="193575643"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575643" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575643">(Apr 10 2020 at 14:39)</a>:</h4>
<p>Left a question for you on that one</p>



<a name="193575646"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575646" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575646">(Apr 10 2020 at 14:39)</a>:</h4>
<p>wait, I thought I would have remembered if we had talked about <em>this</em> in lang team meeting last night</p>



<a name="193575657"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575657" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575657">(Apr 10 2020 at 14:39)</a>:</h4>
<p>we didn't have the time</p>



<a name="193575671"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575671" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575671">(Apr 10 2020 at 14:39)</a>:</h4>
<p>the lang team aspect was the fact that the attribute semantics is visible in the source text</p>



<a name="193575730"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575730" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575730">(Apr 10 2020 at 14:40)</a>:</h4>
<p>so 1. is it a bug about how <code>#![forbid(X)] #![allow(X)]</code> is handled today</p>



<a name="193575757"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575757" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575757">(Apr 10 2020 at 14:40)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> sure; but is there a design question re. the semantics?</p>



<a name="193575771"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575771" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575771">(Apr 10 2020 at 14:40)</a>:</h4>
<p>and 2. should we strive to ensure the command line lint handling matches the source level attribute lint handling</p>



<a name="193575793"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575793" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575793">(Apr 10 2020 at 14:40)</a>:</h4>
<p>ah I see, <span class="user-mention" data-user-id="120791">@RalfJ</span> has commented further since then</p>



<a name="193575805"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575805" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575805">(Apr 10 2020 at 14:41)</a>:</h4>
<p>and that scope levels are relevant</p>



<a name="193575831"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575831" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575831">(Apr 10 2020 at 14:41)</a>:</h4>
<p>I believe both instances Ralf has mentioned re. attributes are bugs</p>



<a name="193575854"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575854" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575854">(Apr 10 2020 at 14:41)</a>:</h4>
<p>(in the current semantics)</p>



<a name="193575885"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575885" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575885">(Apr 10 2020 at 14:41)</a>:</h4>
<p>okay well if everyone is probably in agreement that this is indeed a bug</p>



<a name="193575909"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575909" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575909">(Apr 10 2020 at 14:42)</a>:</h4>
<p>then it probably can be retagged as just T-compiler</p>



<a name="193575970"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193575970" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193575970">(Apr 10 2020 at 14:42)</a>:</h4>
<p>and I'm inclined to remove T-lang from the issue then. I mostly wanted to make sure that they were onboard for changing things here, since I think the attribute (mis)handling is ... old ...?</p>



<a name="193576009"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576009" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576009">(Apr 10 2020 at 14:42)</a>:</h4>
<p>(and that this therefore would be a breaking change, though one that I suspect will not matter much in practice...)</p>



<a name="193576011"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576011" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576011">(Apr 10 2020 at 14:42)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> happy to discuss it at T-Lang if you wish though</p>



<a name="193576038"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576038" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> simulacrum <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576038">(Apr 10 2020 at 14:43)</a>:</h4>
<p>yeah the only reason why it might break people is if they're doing e.g.</p>
<div class="codehilite"><pre><span></span>// #![forbid(warnings)]
// #![deny(unused)]
</pre></div>



<a name="193576039"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576039" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576039">(Apr 10 2020 at 14:43)</a>:</h4>
<p>if you believe that is necessary; but it would be good to leave a clarifying comment on issue though</p>



<a name="193576044"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576044" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576044">(Apr 10 2020 at 14:43)</a>:</h4>
<p>shrug</p>



<a name="193576055"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576055" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576055">(Apr 10 2020 at 14:43)</a>:</h4>
<p>I do think a clarifying comment is necessary</p>



<a name="193576060"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576060" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576060">(Apr 10 2020 at 14:43)</a>:</h4>
<p>and I no longer am certain it needs discussion at T-lang meeting</p>



<a name="193576061"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576061" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576061">(Apr 10 2020 at 14:43)</a>:</h4>
<p>(N.B. this is a lint, so not breaking in the RFC 1122 sense)</p>



<a name="193576065"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576065" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576065">(Apr 10 2020 at 14:43)</a>:</h4>
<p>I'll follow up later.</p>



<a name="193576121"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576121" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576121">(Apr 10 2020 at 14:44)</a>:</h4>
<p>Its in the <em>handling</em> of lints... it seems like thats more fundamental, no?</p>



<a name="193576130"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576130" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576130">(Apr 10 2020 at 14:44)</a>:</h4>
<p>maybe I misunderstnad. but we don't need to debate that now</p>



<a name="193576164"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576164" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576164">(Apr 10 2020 at 14:44)</a>:</h4>
<p>alright</p>



<a name="193576189"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576189" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576189">(Apr 10 2020 at 14:44)</a>:</h4>
<p>nom 6/8: "WIP toward LLVM Code Coverage for Rust" <a href="https://github.com/rust-lang/rust/issues/70680" title="https://github.com/rust-lang/rust/issues/70680">#70680</a></p>



<a name="193576214"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576214" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576214">(Apr 10 2020 at 14:45)</a>:</h4>
<p>I think this one should be bumped to MCP / design meeting</p>



<a name="193576244"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576244" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576244">(Apr 10 2020 at 14:45)</a>:</h4>
<p><span class="user-mention" data-user-id="119009">@eddyb</span> has some concerns</p>



<a name="193576267"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576267" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576267">(Apr 10 2020 at 14:45)</a>:</h4>
<p>yeah I don't think we can resolve the Q's here in a quick triage session</p>



<a name="193576283"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576283" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576283">(Apr 10 2020 at 14:45)</a>:</h4>
<p>I suspect a MCP will fit</p>



<a name="193576310"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576310" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576310">(Apr 10 2020 at 14:45)</a>:</h4>
<p>but ... it also seems like it is undergoing active redesign?</p>



<a name="193576332"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576332" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576332">(Apr 10 2020 at 14:46)</a>:</h4>
<p>MCP would make me happy</p>



<a name="193576342"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576342" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576342">(Apr 10 2020 at 14:46)</a>:</h4>
<p>Lang team and libs team might need to be consulted, if this is ever to reach stable</p>



<a name="193576365"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576365" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576365">(Apr 10 2020 at 14:46)</a>:</h4>
<p>(based on feedback provided)</p>



<a name="193576404"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576404" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576404">(Apr 10 2020 at 14:46)</a>:</h4>
<p>I have opinions because I almost got paid to do this in the past and did research on approaches and technical details</p>



<a name="193576420"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576420" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576420">(Apr 10 2020 at 14:46)</a>:</h4>
<p>so maybe the right answer here is to 1. advertise this PR to the T-compiler team at large (which we are doing here), and 2. tell PR author that we think a MCP is warranted.</p>



<a name="193576443"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576443" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576443">(Apr 10 2020 at 14:46)</a>:</h4>
<p>but it's probably more important that <em>other</em> (than me) people think the design is good</p>



<a name="193576446"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576446" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576446">(Apr 10 2020 at 14:46)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> sgtm</p>



<a name="193576456"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576456" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576456">(Apr 10 2020 at 14:46)</a>:</h4>
<p>okay. I can follow up there</p>



<a name="193576486"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576486" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576486">(Apr 10 2020 at 14:47)</a>:</h4>
<p>nom 7/8: "Use the niche optimization if other variant are small enough" <a href="https://github.com/rust-lang/rust/issues/70477" title="https://github.com/rust-lang/rust/issues/70477">#70477</a></p>



<a name="193576487"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576487" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576487">(Apr 10 2020 at 14:47)</a>:</h4>
<p><span class="user-mention" data-user-id="119009">@eddyb</span> I think your concerns are pretty valid and important that we listen to you in particular</p>



<a name="193576538"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576538" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576538">(Apr 10 2020 at 14:47)</a>:</h4>
<p>oh <a href="https://github.com/rust-lang/rust/issues/70477" title="https://github.com/rust-lang/rust/issues/70477">#70477</a> is pretty cool</p>



<a name="193576549"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576549" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576549">(Apr 10 2020 at 14:47)</a>:</h4>
<p>but I don't have the energy to fight people who want to their own thing</p>



<a name="193576650"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576650" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576650">(Apr 10 2020 at 14:48)</a>:</h4>
<p>at least with <a href="https://github.com/rust-lang/rust/issues/70477" title="https://github.com/rust-lang/rust/issues/70477">#70477</a> I can keep finding edge cases for them to consider :P</p>



<a name="193576678"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576678" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576678">(Apr 10 2020 at 14:48)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> see the two bullet-points in <a href="https://github.com/rust-lang/rust/pull/70477#issuecomment-607725781" title="https://github.com/rust-lang/rust/pull/70477#issuecomment-607725781">https://github.com/rust-lang/rust/pull/70477#issuecomment-607725781</a></p>



<a name="193576701"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576701" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576701">(Apr 10 2020 at 14:49)</a>:</h4>
<p>that is my main concern with their approach</p>



<a name="193576721"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576721" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576721">(Apr 10 2020 at 14:49)</a>:</h4>
<p>yeah I saw that comment and considered quoting it here, thanks for linking it</p>



<a name="193576743"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576743" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576743">(Apr 10 2020 at 14:49)</a>:</h4>
<p>so it seems like part of the issue (maybe the only issue) ...</p>



<a name="193576767"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576767" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576767">(Apr 10 2020 at 14:49)</a>:</h4>
<p>is that the approached encoded in the PR attempts to ensure that it always picks a better choice</p>



<a name="193576832"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576832" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576832">(Apr 10 2020 at 14:50)</a>:</h4>
<blockquote>
<p>I want to land this, but I'm not comfortable with it unless one of these two things happen:<br>
- the implementation gets a formal model, where we can prove things about all possible cases<br>
- we check instead of assuming the conditions are sufficient</p>
</blockquote>
<p>I think this is pretty reasonable; more soundness holes is not something we need atm <span aria-label="slight smile" class="emoji emoji-1f642" role="img" title="slight smile">:slight_smile:</span></p>



<a name="193576833"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576833" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576833">(Apr 10 2020 at 14:50)</a>:</h4>
<p>but it is unproven that it is actually improving</p>



<a name="193576864"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576864" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576864">(Apr 10 2020 at 14:50)</a>:</h4>
<p><span class="user-mention" data-user-id="126931">@centril</span> at least no layout should be unsound :P</p>



<a name="193576867"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576867" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576867">(Apr 10 2020 at 14:50)</a>:</h4>
<p>but to be clear</p>



<a name="193576874"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576874" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576874">(Apr 10 2020 at 14:50)</a>:</h4>
<p>its not injecting soundness holes</p>



<a name="193576888"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576888" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576888">(Apr 10 2020 at 14:50)</a>:</h4>
<p>just potential size regressions, right?</p>



<a name="193576900"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576900" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576900">(Apr 10 2020 at 14:50)</a>:</h4>
<p>(which is bad, but not bad on the level of unsound)</p>



<a name="193576919"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576919" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576919">(Apr 10 2020 at 14:50)</a>:</h4>
<p>and the approach <span class="user-mention" data-user-id="119009">@eddyb</span> has been advocating</p>



<a name="193576935"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576935" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576935">(Apr 10 2020 at 14:51)</a>:</h4>
<p>oh; if that's the case then...</p>



<a name="193576948"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576948" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576948">(Apr 10 2020 at 14:51)</a>:</h4>
<p>is instead to just compute "both" layouts (which in general ... might be N layouts, no?)</p>



<a name="193576961"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576961" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576961">(Apr 10 2020 at 14:51)</a>:</h4>
<p>and choose the best one? Does that sound right?</p>



<a name="193576969"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576969" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576969">(Apr 10 2020 at 14:51)</a>:</h4>
<p>yeah</p>



<a name="193576997"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193576997" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193576997">(Apr 10 2020 at 14:51)</a>:</h4>
<p>So we would speculate, that is</p>



<a name="193577007"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577007" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577007">(Apr 10 2020 at 14:51)</a>:</h4>
<p>the reason I even bring up "checking instead of assuming" is that I've tried to come up with all the conditions for doing this the "clever predicate" way</p>



<a name="193577031"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577031" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577031">(Apr 10 2020 at 14:52)</a>:</h4>
<p>and it's a nightmare to reason about</p>



<a name="193577108"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577108" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577108">(Apr 10 2020 at 14:52)</a>:</h4>
<p>and in other parts of the compiler we just collect "candidates" and pick from there</p>



<a name="193577110"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577110" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577110">(Apr 10 2020 at 14:52)</a>:</h4>
<p>I think <span class="user-mention" data-user-id="116009">@nikomatsakis</span> chimed in on the ticket with support for <span class="user-mention" data-user-id="119009">@eddyb</span> 's feedback</p>



<a name="193577155"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577155" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577155">(Apr 10 2020 at 14:52)</a>:</h4>
<p>which I respect even more now, that I know places where not doing that has caused a lot of wasted time trying to think through "clever decision-making logic"</p>



<a name="193577167"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577167" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577167">(Apr 10 2020 at 14:52)</a>:</h4>
<p>and I am of a similar mindset. Even if the PR author believes the conditions they have encoded are easy enough to reason about, we need to think of long term maintenance</p>



<a name="193577204"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577204" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577204">(Apr 10 2020 at 14:53)</a>:</h4>
<p>another thing is that I've received complaints over the years that the layout code is a complex mess</p>



<a name="193577210"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577210" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577210">(Apr 10 2020 at 14:53)</a>:</h4>
<p>the only concern I have is</p>



<a name="193577220"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577220" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577220">(Apr 10 2020 at 14:53)</a>:</h4>
<p>how expensive is it to try multiple layouts?</p>



<a name="193577230"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577230" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577230">(Apr 10 2020 at 14:53)</a>:</h4>
<p>which is mostly a byproduct of what it grew out of (the old straight-to-LLVM ADT layout logic)</p>



<a name="193577243"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577243" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577243">(Apr 10 2020 at 14:53)</a>:</h4>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> I think it would be easy to measure that, just nobody has done it</p>



<a name="193577251"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577251" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577251">(Apr 10 2020 at 14:53)</a>:</h4>
<p>it should not have downstream effects, at least</p>



<a name="193577302"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577302" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577302">(Apr 10 2020 at 14:54)</a>:</h4>
<p>i.e. I was briefly worried about exponential blowup</p>



<a name="193577307"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577307" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577307">(Apr 10 2020 at 14:54)</a>:</h4>
<p>from nested enum types</p>



<a name="193577319"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577319" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577319">(Apr 10 2020 at 14:54)</a>:</h4>
<p>yeah, no, once you pick a layout it's done</p>



<a name="193577358"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577358" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577358">(Apr 10 2020 at 14:54)</a>:</h4>
<p>but that should not occur, because we should compute the layout for an enum and stick with it regardless of any context it occurs in</p>



<a name="193577365"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577365" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577365">(Apr 10 2020 at 14:54)</a>:</h4>
<p>so yeah</p>



<a name="193577412"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577412" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577412">(Apr 10 2020 at 14:55)</a>:</h4>
<p>I'm happy to leave a note here too</p>



<a name="193577428"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577428" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577428">(Apr 10 2020 at 14:55)</a>:</h4>
<p>the way we'd measure this is to not early-return if we found a niche candidate, but just stash it in a variable and check it after we compute the regular layout</p>



<a name="193577447"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577447" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577447">(Apr 10 2020 at 14:55)</a>:</h4>
<p>its a little worrisome that the PR author has been so adamantly opposed to incorporating your suggestion</p>



<a name="193577454"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577454" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577454">(Apr 10 2020 at 14:55)</a>:</h4>
<p>I may have even suggested this exact thing to the PR author or someone else in the past and nobody has tried it</p>



<a name="193577483"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577483" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577483">(Apr 10 2020 at 14:55)</a>:</h4>
<p>/me should just go for it, it's like, what, a 5-line change?</p>



<a name="193577495"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577495" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577495">(Apr 10 2020 at 14:55)</a>:</h4>
<p>(this is how I can spend weeks in weeds)</p>



<a name="193577533"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577533" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577533">(Apr 10 2020 at 14:56)</a>:</h4>
<p>anyway, I can leave a note here too</p>



<a name="193577564"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577564" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577564">(Apr 10 2020 at 14:56)</a>:</h4>
<p><span class="user-mention silent" data-user-id="116083">pnkfelix</span> <a href="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193577447" title="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193577447">said</a>:</p>
<blockquote>
<p>its a little worrisome that the PR author has been so adamantly opposed to incorporating your suggestion</p>
</blockquote>
<p>at least I'm glad that they try to understand and resolve every edge case I throw at them</p>



<a name="193577567"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577567" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577567">(Apr 10 2020 at 14:56)</a>:</h4>
<p>after I read the comment thread more carefully, to better understand the PR author's Point of View</p>



<a name="193577603"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577603" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577603">(Apr 10 2020 at 14:56)</a>:</h4>
<p>nom 8/8: "Should enum discriminants have generics in scope?" <a href="https://github.com/rust-lang/rust/issues/70453" title="https://github.com/rust-lang/rust/issues/70453">#70453</a></p>



<a name="193577608"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577608" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577608">(Apr 10 2020 at 14:57)</a>:</h4>
<p>this is once again a lang team nomination</p>



<a name="193577615"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577615" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577615">(Apr 10 2020 at 14:57)</a>:</h4>
<p>I believe</p>



<a name="193577629"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577629" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577629">(Apr 10 2020 at 14:57)</a>:</h4>
<p>yeah</p>



<a name="193577636"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577636" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577636">(Apr 10 2020 at 14:57)</a>:</h4>
<p>this time just to check your boxes</p>



<a name="193577644"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577644" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577644">(Apr 10 2020 at 14:57)</a>:</h4>
<p>(whcih was discussed last night and is in lang team prompt for FCP now)</p>



<a name="193577650"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577650" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577650">(Apr 10 2020 at 14:57)</a>:</h4>
<p>btw if someone is bored, here's a bit of layout math that the author led me to find out <a href="https://github.com/rust-lang/rust/pull/70477#discussion_r403269107" title="https://github.com/rust-lang/rust/pull/70477#discussion_r403269107">https://github.com/rust-lang/rust/pull/70477#discussion_r403269107</a></p>



<a name="193577652"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577652" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577652">(Apr 10 2020 at 14:57)</a>:</h4>
<p>so e.g., <span class="user-mention" data-user-id="116083">@pnkfelix</span>'s box, hint hint <span aria-label="slight smile" class="emoji emoji-1f642" role="img" title="slight smile">:slight_smile:</span></p>



<a name="193577697"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577697" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577697">(Apr 10 2020 at 14:57)</a>:</h4>
<p>so okay, that's all the nominations and we're basically out of time</p>



<a name="193577759"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577759" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> pnkfelix <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577759">(Apr 10 2020 at 14:58)</a>:</h4>
<p>I'll go back through the notes here and write up the comments I promised.</p>



<a name="193577774"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577774" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577774">(Apr 10 2020 at 14:58)</a>:</h4>
<p>someone should write a paper on the algebra of layouts</p>



<a name="193577787"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577787" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577787">(Apr 10 2020 at 14:58)</a>:</h4>
<p>Excellent, thanks <span class="user-mention" data-user-id="116083">@pnkfelix</span></p>



<a name="193577792"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577792" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577792">(Apr 10 2020 at 14:58)</a>:</h4>
<p>and how alignments interact with everything</p>



<a name="193577822"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577822" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577822">(Apr 10 2020 at 14:58)</a>:</h4>
<p><span class="user-mention" data-user-id="119009">@eddyb</span>  interesting; seems like that could be a MSc thesis even</p>



<a name="193577835"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577835" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577835">(Apr 10 2020 at 14:59)</a>:</h4>
<p>or BSc if not</p>



<a name="193577876"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193577876" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193577876">(Apr 10 2020 at 14:59)</a>:</h4>
<p>(it's likely that on average, most permutations of field order result in the same number of padding bytes, it's really hard to even make examples which go against that)</p>



<a name="193578063"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193578063" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> centril <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193578063">(Apr 10 2020 at 15:00)</a>:</h4>
<p><span aria-label="wave" class="emoji emoji-1f44b" role="img" title="wave">:wave:</span> y'all</p>



<a name="193709548"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193709548" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193709548">(Apr 12 2020 at 11:41)</a>:</h4>
<p><span class="user-mention silent" data-user-id="116083">pnkfelix</span> <a href="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193577167" title="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193577167">said</a>:</p>
<blockquote>
<p>and I am of a similar mindset. Even if the PR author believes the conditions they have encoded are easy enough to reason about, we need to think of long term maintenance</p>
</blockquote>
<p><span class="user-mention" data-user-id="116083">@pnkfelix</span> <span class="user-mention" data-user-id="116009">@nikomatsakis</span> so here's some good news, I went and tried doing the most minimal "two layouts cost measurement" version of this, and it's largely perf-neutral: <a href="https://github.com/rust-lang/rust/pull/71045#issuecomment-612579390" title="https://github.com/rust-lang/rust/pull/71045#issuecomment-612579390">https://github.com/rust-lang/rust/pull/71045#issuecomment-612579390</a></p>



<a name="193709611"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193709611" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193709611">(Apr 12 2020 at 11:42)</a>:</h4>
<p>the PR author also did something similar, but got a regression: <a href="https://github.com/rust-lang/rust/pull/70477#issuecomment-612493899" title="https://github.com/rust-lang/rust/pull/70477#issuecomment-612493899">https://github.com/rust-lang/rust/pull/70477#issuecomment-612493899</a></p>



<a name="193709619"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/193709619" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> eddyb <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#193709619">(Apr 12 2020 at 11:42)</a>:</h4>
<p>so we now have to figure out where the slowdown comes from. which seems productive</p>



<a name="194626627"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/131828-t-compiler/topic/ad%20hoc%20triage%20meeting%202020.04.10%20%2354818/near/194626627" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Peter Rabbit <a href="https://rust-lang.github.io/zulip_archive/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818.html#194626627">(Apr 20 2020 at 01:28)</a>:</h4>
<p><span class="user-mention silent" data-user-id="116083">pnkfelix</span> <a href="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193574688" title="#narrow/stream/131828-t-compiler/topic/ad.20hoc.20triage.20meeting.202020.2E04.2E10.20.2354818/near/193574688">said</a>:</p>
<blockquote>
<p>I can reach out to retep, see if they object to being our domain expert here</p>
</blockquote>
<p>I don't object.</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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